CVE-2026-63947 Linux CVE debrief

Who should care

Linux kernel developers, Linux distribution maintainers, and users of Linux-based systems with Bluetooth HIDP devices should be aware of this vulnerability and take necessary actions to mitigate it. This includes reviewing and applying the kernel patch, verifying Linux kernel and distribution versions for updates, and monitoring Bluetooth HIDP device usage and system logs for suspicious activity.

Technical summary

The Linux kernel's Bluetooth HIDP implementation is vulnerable to an out-of-bounds read due to a missing length check in the hidp_input_report() function. This can be exploited by a paired device sending a truncated packet, potentially leading to phantom key presses or spurious mouse movement. The issue is resolved by replacing open-coded length tracking and pointer arithmetic with skb_pull_data() calls, which return NULL if the requested bytes are not present.

Defensive priority

Medium

Recommended defensive actions

• Review and apply the kernel patch
• Verify Linux kernel and distribution versions for updates
• Monitor Bluetooth HIDP device usage and system logs for suspicious activity
• Consider implementing additional logging and monitoring for kernel events
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-07-19T16:17:13.337Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the official CVE record and vendor guidance.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.